DRT: filter unsupported rules at io and fix minarea in FlexGC

[openroad-ci]

Summary

refactor(drt): filter unsupported rules at IO instead of GC

Unsupported LEF58_AREA and LEF58_CUTSPACING sub-branches were accepted in io.cpp but warned per-invocation in GC — noisy and wasteful. Reject them once at parse time, skip storing. In addition, the logic for checking the LEF58_AREA rules was flawed.

• LEF58_AREA: filter EXCEPTMINWIDTH, EXCEPTEDGELENGTH, EXCEPTMINSIZE, EXCEPTSTEP, MASK, LAYER branches in io.cpp
• LEF58_SPACING ADJACENTCUTS: filter EXACTALIGNED, EXCEPTSAMEPGNET, TO ALL, SIDEPARALLELOVERLAP, SAMEMASK branches in io.cpp
• LEF58_SPACING LAYER: filter STACK, ORTHOGONALSPACING, SHORTEDGEONLY, WIDTH, PARALLEL, EDGELENGTH, EXTENSION, ABOVEWIDTH, MASKOVERLAP, WRONGDIRECTION branches in io.cpp
• Fix LEF58_AREA check logic: sort by area descending, patch once for largest applicable constraint; separate rectWidth constraints into own sorted vector for correct priority
• Remove dead check_rect_width flag and no-op edge loop from GC
• Drop redundant unsupported-branch warnings and stubs from GC

Type of Change

• Bug fix
• Breaking change
• Refactoring

Impact

This is expected to change how DRT patches for min area rules.

Verification

• I have verified that the local build succeeds (./etc/Build.sh).
• I have run the relevant tests and they pass.
• My code follows the repository's formatting guidelines.
• I have signed my commits (DCO).

[gemini-code-assist]

Code Review

This pull request refactors the handling of LEF58 area constraints by separating them into general area and rectwidth-specific lists, ensuring they are sorted for optimized checking. It also updates the parser to skip unsupported LEF58 rule branches and refactors the geometric verification logic. Feedback identifies a logic bug in the area check where non-rectangle shapes could prematurely skip constraints, notes that RECTWIDTH comparisons should be inclusive to match the LEF58 specification, and highlights a potential null pointer dereference for drWorker_.

[github-actions]

clang-tidy made some suggestions

[github-actions]

warning: no header providing "std::ranges::lower_bound" is directly included [misc-include-cleaner]

src/drt/src/db/tech/frLayer.h:5:

- #include <algorithm>
+ #include <bits/ranges_algo.h>
+ #include <algorithm>